GE CT-9800

GE MEDICAL SYSTEMS CT 9800 QUICK SYSTEM
Rev. 6 Direction 18000
6-10-3
10-3 Table To Gantry Alignment
Before adjusting the alignment lights, verify that the table and gantry are properly aligned per section 11.
10-4 Laser Alignment Tool Setup
To properly align and center the alignment tool in the scan plane, proceed as follows:
1. Install the alignment tool on the phantom holder.
2. Level the tool until the bubble on top of the tool is centered using the adjustment screws (Ill. 6-10-2).
3. Turn on the alignment lights.
4. Advance the table into the gantry until the internal axial beam falls into the notched portion of the teflon end
on the tool.
NOTE: The internal lights have not been adjusted yet and are merely used to approximately
locate the teflon end in the scan plane.
5. Raise the table until the teflon end is roughly at ISO (i.e., coronal lights can be used to mark the approximate
location).
NOTE: The coronal lights have not been adjusted yet and are merely used to approximately
locate the teflon end at ISO.
6. At M-level, enter the Scan Program and perform a scout scan at the following technique:
Azimuth : 0°
Table Speed : Fast
Starting Location : -350 mm.(minus 350)
Ending Location : 50 mm.
kV : 120
mA : 100
Tilt : 0°
7. As shown in Ill. 6-10-3, verify that the tool is perpendicular to the scan plane using the Line Cursor Function
on the console keyboard.
NOTE: If perpendicular alignment of the tool cannot be obtained subsequent to using the
adjustment screws on the tool, check table - to - gantry alignment per section 11.
8. At this point the tool should be perpendicular to the scan plane and the teflon end roughly centered at ISO.
Use the centering program in Cal Check and center the teflon end of the tool to within ± 0.12 mm. Use the
following technique:
Water Cal
1.5 mm. aperture
120 kV
100 mA
9. Perform another scout scan using the following technique:
Azimuth : 0°
Table Speed : Fast
Starting Location : -350 mm.(minus 350)